Hundreds of people enjoyed a memorabilia display and bush dance on Saturday, with students hosting a back to the '60s day on Friday.

Teacher and event co-ordinator Lauren Parker said organisers were thrilled with the turnout.

While many Illawarra public schools have celebrated much longer milestones, there were genuine fears Warilla North PS would not reach its 50th year.

In 2010, the school had received $850,000 for a library and upgrade of the covered outdoor learning area through the Building the Education Revolution program, but asbestos was discovered during this work forcing the school's students to transfer to either Mt Warrigal or Barrack Heights public schools.

There were concerns the school would be forced to close, due to declining numbers and a hefty maintenance bill.

The former member for Shellharbour, Lylea McMahon, launched a petition to save the school and more than 1000 signatures were obtained by parents, including that of former prime minister John Howard.

The NSW government gave $4.5 million towards a major upgrade and became home to the Department of Education's district office.

In the 1970s, Warilla North reportedly had one of the largest primary school populations in NSW with about 1500 students - and lots of demountable buildings - at one stage.

School principal Wayne Osborne said today the school had 126 students, with numbers on the rise this year.

The school has been praised for its work through the Early Action for Success program.